A mathematical model for initial design iterations and feasibility studies of oxygen membrane reactors by minimizing Gibbs free energy

Abstract

Ceramic Membrane Reactors offer an opportunity towards the transition to renewable energies and defossilized economies by efficiently coupling chemical reactions and heat utilization. To identify viable processes, mathematical models are needed that allow a straightforward assessment. In this study, a generalized model is presented that can be applied to membrane reactor concepts using a mixed oxygen transport membrane. The model assumes chemical equilibrium which is realized by minimizing the Gibbs free energy in the individual reaction chambers. Both reaction chambers are coupled by the Wagner equation to account for the oxygen ion flux through the membrane. Experimental data from the literature were used to validate the model for water splitting, partial oxidation of methane, and the coupling of these two processes. The model allows to investigate various process parameters such as oxygen flux and gas compositions, making the model particularly suitable for feasibility studies and initial design iterations for new reactor developments.